There is definitely more than one cheater per game, quite regularly whole teams are cheating (nearly every match I used to play in fact). Cheating has become so rampant in this game that I honestly cannot stand to play it anymore. It is nothing more than an aggravating exercise in frustration. There was an aimbot hack 4 hours after this game was released, and there has been nothing done to stop people using it since then it seems. You are losing players/customers left and right due to this issue. The vast majority of the cheaters will keep playing the game even if they can no longer cheat, but the majority of the non cheaters wil be looking elsewhere to spend their dollars. It is in your best interest to do something about the problem so why aren't you?!?
What most people fail to realize is that the cheaters and people advertising cheats are part of Activision's plan for MW3.
They released the game with P2P matchmaking (IWNet) while being fully aware that it would leave MW3 completely open to hackers of all kinds.
The only effort they make to combat hacking/cheating is BanCandy, who surprise surprise, needs so much video evidence that only the most blatantly obvious cheaters are banned (maybe 2% of them)
Don't forget that once DLC was released Activision stopped looking at the cheat reports completely. They will renew their efforts just before the 2nd DLC pack launches, then they will stop again.
See the reason they intentionally set MW3 up this way was so that they could make money off of selling hacks. They either run hack sites themselves (most likely) or they are in business with a hack provider (less likely) but either way it's one of the two.
There is no other reason whatsoever why they would've intentionally released MW3 with such an open hacker friendly matchmaking system like IWNet. (Oh and remember VAC only works with dedi's, something else Activision was well aware of prior to MW2 launch)
^^ This is the kind of company Activision is. Until their CEO Bobby Kotick is fired or gets hit by a bus, they will continue to lie, scam, cheat, and screw over everyone from employee to customer.